Email Security Engineer - Contract

We are seeking a hands-on Email Security Engineer to support the delivery and operational uplift of Optus email security. The contractor will work closely with Luc and the Director, Data Protection & Email Security, to strengthen outbound controls, complete Mimecast implementation activities and support the controlled decommissioning of Trend Micro email security capabilities.

This is a delivery-focused role for someone who can operate at both engineering and operational levels — designing changes, implementing them, troubleshooting issues, documenting outcomes and handing over stable services to BAU teams.

Key responsibilities

• Execute configuration and engineering changes in a controlled manner.
• Coordinate testing with technical teams and business stakeholders.
• Develop runbooks, technical procedures, support models and knowledge-transfer materials.
• Monitor post-change outcomes and recommend further tuning.
• Escalate issues early and drive actions through to completion.
• Design, implement and validate the Mimecast outbound mail flow.
• Review outbound routing, controls, policies, authentication and delivery behaviour.
• Identify and close gaps across data protection, malware, impersonation, URL and policy enforcement controls.
• Troubleshoot mail-flow issues across Mimecast, Microsoft 365 and downstream or third-party systems.
• Support testing, cutover planning, monitoring and rollback readiness.
• Map current Trend Micro email security capabilities, integrations, dependencies and traffic flows.
• Define the migration and decommissioning sequence in coordination with the Mimecast target state.
• Remove or retire legacy configurations, rules and integrations safely.
• Validate that required protection and mail-flow outcomes remain in place after each change.
• Support defect resolution, rollback planning, evidence capture and final closure of the decommissioning work.

• Strong hands-on experience administering and engineering Email Security.
• Demonstrated experience with outbound email security and enterprise mail-flow troubleshooting.
• Practical experience implementing email journaling and validating message coverage.
• Experience uplifting email security policies and managing controlled exceptions.
• Experience with Microsoft 365 / Exchange Online mail flow, connectors, transport rules and message tracing.
• Experience retiring or migrating legacy email security platforms, preferably Trend Micro.
• Working knowledge of SPF, DKIM, DMARC, SMTP, DNS and email authentication.
• Ability to produce clear technical documentation and operational handover material.

Why NCS?

This is a place for people who like to get stuck in, bring ideas to life and make things happen.

You’ll work alongside experienced people who care about what they do, contribute to meaningful work and have the support to keep learning and grow your career.

Whether you want to deepen your expertise, explore something new or take your career in a different direction, there’s room to make it your own.

We value Adventure, Excellence, Integrity, Ownership and Unity — bringing curiosity, collaboration and accountability to the way we work with our clients and each other.

Ready to make extraordinary happen?

We’d love to hear from you.

We celebrate diversity and inclusion

We value the different perspectives, experiences and strengths our people bring. We’re committed to an inclusive workplace where everyone has the opportunity to contribute, grow and succeed, and to providing equal employment opportunities and reasonable adjustments throughout the recruitment process.

Important information

Applicants will need valid Australian work rights and may be required to undergo relevant background, probity and police checks.

Agencies: NCS accepts candidate submissions only from agencies on our preferred supplier panel through the NCS Agency Portal.